And I have the same question too…
The same pattern is repeated in Chapter 10: categories.asObservable(), events.asObservable() where both categories & events are BehaviorRelay.
The question was asked at least twice:
- Please explain when to use asObservable() in Chapter 4, page 90
- Chapter 4 - BehaviorRelay as observable?
with no definitive answer.
The only insight was given by @jecht83
seems that the intention to use it is to make clear to the user that only changes in
self.imagesare being observed and nothing else
Somebody could verify/confirm aboves?
That it is only about “making intention clear”.